"""
    sphinx.builders.xml
    ~~~~~~~~~~~~~~~~~~~

    Docutils-native XML and pseudo-XML builders.

    :copyright: Copyright 2007-2020 by the Sphinx team, see AUTHORS.
    :license: BSD, see LICENSE for details.
"""

from os import path
from typing import Any, Dict, Iterator, Set, Type, Union

from docutils import nodes
from docutils.io import StringOutput
from docutils.nodes import Node
from docutils.writers.docutils_xml import XMLTranslator

from sphinx.application import Sphinx
from sphinx.builders import Builder
from sphinx.locale import __
from sphinx.util import logging
from sphinx.util.osutil import ensuredir, os_path
from sphinx.writers.xml import XMLWriter, PseudoXMLWriter


logger = logging.getLogger(__name__)


class XMLBuilder(Builder):
    """
    Builds Docutils-native XML.
    """
    name = 'xml'
    format = 'xml'
    epilog = __('The XML files are in %(outdir)s.')

    out_suffix = '.xml'
    allow_parallel = True

    _writer_class = XMLWriter  # type: Union[Type[XMLWriter], Type[PseudoXMLWriter]]
    default_translator_class = XMLTranslator

    def init(self) -> None:
        pass

    def get_outdated_docs(self) -> Iterator[str]:
        for docname in self.env.found_docs:
            if docname not in self.env.all_docs:
                yield docname
                continue
            targetname = path.join(self.outdir, docname + self.out_suffix)
            try:
                targetmtime = path.getmtime(targetname)
            except Exception:
                targetmtime = 0
            try:
                srcmtime = path.getmtime(self.env.doc2path(docname))
                if srcmtime > targetmtime:
                    yield docname
            except OSError:
                # source doesn't exist anymore
                pass

    def get_target_uri(self, docname: str, typ: str = None) -> str:
        return docname

    def prepare_writing(self, docnames: Set[str]) -> None:
        self.writer = self._writer_class(self)

    def write_doc(self, docname: str, doctree: Node) -> None:
        # work around multiple string % tuple issues in docutils;
        # replace tuples in attribute values with lists
        doctree = doctree.deepcopy()
        for node in doctree.traverse(nodes.Element):
            for att, value in node.attributes.items():
                if isinstance(value, tuple):
                    node.attributes[att] = list(value)
                value = node.attributes[att]
                if isinstance(value, list):
                    for i, val in enumerate(value):
                        if isinstance(val, tuple):
                            value[i] = list(val)
        destination = StringOutput(encoding='utf-8')
        self.writer.write(doctree, destination)
        outfilename = path.join(self.outdir, os_path(docname) + self.out_suffix)
        ensuredir(path.dirname(outfilename))
        try:
            with open(outfilename, 'w', encoding='utf-8') as f:
                f.write(self.writer.output)
        except OSError as err:
            logger.warning(__("error writing file %s: %s"), outfilename, err)

    def finish(self) -> None:
        pass


class PseudoXMLBuilder(XMLBuilder):
    """
    Builds pseudo-XML for display purposes.
    """
    name = 'pseudoxml'
    format = 'pseudoxml'
    epilog = __('The pseudo-XML files are in %(outdir)s.')

    out_suffix = '.pseudoxml'

    _writer_class = PseudoXMLWriter


def setup(app: Sphinx) -> Dict[str, Any]:
    app.add_builder(XMLBuilder)
    app.add_builder(PseudoXMLBuilder)

    app.add_config_value('xml_pretty', True, 'env')

    return {
        'version': 'builtin',
        'parallel_read_safe': True,
        'parallel_write_safe': True,
    }
